<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>

</head>
<body>
<a href="http://www.baidu.com">百度</a>
<script>
  var a = document.querySelector('a');

  a.addEventListener('click', function (e) {
    e.preventDefault();
  })
</script>
</body>
</html>